THE IMPACT OF ROOF TOP SOLAR PV UNDER NET ENERGY · PDF fileTHE IMPACT OF ROOF TOP SOLAR PV...
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THE IMPACT OF ROOF TOP SOLAR PV UNDER NET ENERGY METERING
PROGRAM ON NATIONAL UTILITY AND PUBLIC IN MALAYSIA
Sansubari CheMud
Tenaga Nasiona Berhad, Level 16 Wisma TNB, 46200 Petaling Jaya, Malaysia
1 INTRODUCTION
Net-energy metering or net metering is a policy that enables electricity customers to connect
their own roof-top solar power generation system to the utility grid and receive credits on
their electricity bills for their roof-top solar energy generation in excess of their electricity
consumption that is exported to the electricity distribution network. The term net-energy
metering refers to the fact that the meter can measure the flow of electricity in bi-directional
within the utility system by feeding the grid when excess power is produced and consume
power from the grid at a later time when their production falls below consumption.
In most utilities’ net metering systems, if the customer generates more electrical energy than
the customer uses from the utility electrical system, the customer will not be paid for that
energy, but the customer receives a ‘credit’, which is applied to future bills. This ‘credit’
can either in the form of ‘kWh’ rolling over to next month bill or some opted for monetary
term that rolled over to coming bill, depending on one country net-energy metering policy.
Many different renewable energy sources may be eligible for net metering credits, solar
rooftop installations are the most common and popular type of renewable energy source
promoted with net-energy metering.
Under most net metering policies, utilities are required to buy a roof-top solar customer’s
excess power at full retail price even though it costs those utilities much less to produce that
electricity themselves, or buy it on the wholesale market.
The point of these policies is to encourage the adoption of distributed solar on residential
and to take advantage of existing surfaces, to generate the energy right where it’s needed,
and to reduce the total electric load during peak hours of the day. Along with increased
efficiency and conservation, roof-top solar generation can reduce the need to build new large
power plants even as the population grows.
Rooftop solar users are still connected to the grid, which is necessary to have net metering,
and also to power their homes at night or when their solar arrays don’t produce enough
power.
Malaysia is about to move into big plan for net-energy metering. Malaysia will be
implementing 500 megawatts (MW) of capacity for net energy metering beginning 2016
until 2020, with 100MW capacity limit a year in Peninsular Malaysia and Sabah. 500MW
of solar capacity is equivalent to 7% of national utility company (TNB) total installed
capacity. The development of major strategic plan for net-energy metering in the country
has to be in holistic manner. The impact to the utility and to the ratepayer has to be assessed
in due diligent.
Statistic indicated that electricity demand growth in Peninsular Malaysia continues to
decline for three consecutive years despite the country’s healthy economic growth.
In 2015, peak demand experienced negative growth for the first time in recorded history.
The system recorded a peak demand of 16,822MW which is 79MW lower than the highest
peak demand of 16,900MW achieved in 2014.
Figure 1: Peninsular Malaysia’s peak demand trend in MW, FY1980 - FY2015 (source: TNB)
Based on initial studies, emerging trends and the advancement of distributed generation
solar technology are seen as the key factors influencing the recent slowdown in electricity
demand growth. The increasing impact of solar PV is seen as a contributor towards reduction
in the overall electricity consumption. This impact will increase even further with the
projected solar capacity of 500MW under Malaysia Net-Energy Metering Program in the
system effective from 2016 onward.
Figure 2: The amount of energy generated by solar is increasing rapidly (source: TNB)
It is important for national utility and the industry to address these challenges urgently.
Delay to do so will cause various impacts towards the national economy and current
Incentive Base Regulation (IBR) which the first step toward national electricity industry
restructuring.
For this reason, it is timely and crucial for the “The Impact of Roof Top Solar PV under
Net Energy Metering Program on National Utility and Public in Malaysia” to be
assessed. It will be a good indicator what net-energy metering could offer in future
Malaysia electricity industry.
2 THE CONCEPT OF NET-ENERGY METERING
Net energy metering allows registered customer with solar installation to generate power
for own consumption and if there is any excess, the power allows to be injected into utility
grid.
The bi-directional meter measures the excess power to the grid and amount of electricity
supplied by utility. The monthly energy bill is calculated using this different.
Net energy metering policies vary from country to country. Malaysia is developing its own
policy.
Fig. 3: Net-energy metering scheme
Electric customers that generate their own electricity from a rooftop solar photovoltaic (PV)
are eligible to participate in a billing arrangement called net metering. The rooftop solar
system produced DC electrical energy and converted to AC through an inverter before fed
into the utility network. The power generated in excess of the owner’s electricity
consumption is fed into the grid through a bi-directional energy meter capable of registering
both import and export of electricity. The arrangement of a net metering system utilizes the
same service line for excess power injection into the grid which is already being used by
the consumer for draw of power from utility network.
Net-Metering allows rooftop solar PV owner to generate electricity and set off the power
produced against the power used from the utility grid and consumer pays only for the “net”
number of units (difference between import and export energy) used each month. In the
event the consumer produces power in excess of his usage in a particular month, the
customer’s energy charge becomes zero and the remaining number of units will be credited
Bi-directional Meter
Excess power
Excess energy to
utility network
Utility
Supply Solar PV
Supply
Load
and carried forward to the following month. Normally most of electricity companies allow
carrying forward the excess electricity generated for up to one year period. Some electric
companies may pay back to the consumer for the extra power if more energy has been
injected into the system than the consumer has used. In Malaysia, there is no real financial
transaction between rooftop solar PV owner and the utility. The credit will be carried
forward to the coming bill and at the end of the year, the credit (should there any) will be
forfeited (write off).
3 DEVELOPMENT OF RENEWABLE ENERGY AND NET-ENERGY METERING
IN MALAYSIA
Under the 8th Malaysia Plan (2000-2005), Malaysian Government has set an objective to
diversified energy mix for electricity generation in Malaysia. In year 2000, Malaysian
Government introduced The Fifth Fuel Policy, which Renewable Energy (RE) has been
identified as Malaysia’s fifth fuel in addition to gas, oil, coal and hydro in electricity
generation mixes. On 11th March 2001, Ministry of Energy, Green Technology and Water
Malaysia (KeTTHA) announced the launching of the Small Renewable Energy Power
(SREP) Program under the umbrella of Special Committee on Renewable Energy (SCORE)
chaired by the minister for KeTTHA. The SREP program has provided access for
renewable energy to the national utility grid with other fiscal package such as import duty
and sales tax exemption, accelerated capital allowances for project investment, simplified
licensing procedures by Suruhanjaya Tenaga (the Energy Commission for Malaysia) and
‘pioneer status’ which waives the project investment from taxable income tax for up to five
years.
Motivated by the SREP program and inspiration from the International Energy Agency
Photovoltaic Power Systems Program’s (PVPS) that solar technology cost can be reduced
significantly whenever there is a double growth of solar market, Malaysian government
decided to focus on Building Integrated Photovoltaic (BIPV) technology application. The
SREP program was expanded to include BIPV in 2003. Subsequently, the national
‘Malaysian BIPV (MBIPV) Project’ was launched on 25 July 2005 by the Minister of
Energy. This initiative is designed to increase the uptake of solar technology and ultimately,
realize solar potentials in Malaysia.
On 31st March 2006, the Malaysia Government announced the inclusion of MBIPV project
into 9th Malaysia Plan (2006-2010) and the project received co-financings from the United
Nation Development Programme/Global Environment Facility (UNDP/GEF) as well as the
private sector. The objective was to create a sustainable solar market in Malaysia that will
generate widespread solar applications, in addition to contributing towards the national
energy policy objectives. Study done by MBIPV team indicated that the energy from BIPV
installation could produce more than 12,000GWh of electricity per year1. National utility,
Tenaga Nasional Berhad (TNB) has agreed to allow grid connection of solar installations
under the MBIPV project to its low voltage (LV) distribution network, and to adopt a “net-
metering” concept for the accounting of solar generated electricity transferred to the
national utility distribution network.
Strong support from national utility has made the MBIPV project overachieved its target.
2,055 kWp of photovoltaic capacity had been commissioned in August 20112. Importantly,
the MBIPV project coupled with the SREP program led to the development of the Malaysia
Renewable Energy and Action Plan which was approved in 2010 and incorporated into the
10th Malaysia Plan (2011 – 2015). This resulted in the 2011 passage of the Renewable
Energy Act, which created a feed-in tariff mechanism and establishment of champion
agency for renewable energy for Malaysia called Sustainable Energy Development
Authority (SEDA). The feed-in tariff applies to indigenous renewable energy resources up
to capacity of 30MW from biomass, biogas, small hydro and solar photovoltaic. The rate
and duration of the feed-in tariff depending on type of technology applied and capacity of
the power plant3. Take up rate for solar PV under Feed-in Tariff mechanism was
overwhelming. Quota for 20MW Solar Photovoltaic for the first released by SEDA
Malaysia in Jun 2013 taken up within hour4.
In August 2015, SEDA Malaysia has announced the introduction of net-energy metering
(NEM) to address the overwhelming demand for solar PV. NEM allows self-consumption
of electricity generated by solar PV system users, while selling the excess energy to utility
company. It was suggested that the NEM quota for residential to be at 20 per cent, industrial
sector (40 per cent) and the remaining for commercial buildings5.
By the introduction of nation-wide net energy program in 2016, Malaysia will become the
first few ASEAN countries introduced net metering. On top, there will be no upfront
financial obligation upon the solar rooftop owner except for the initial one-time charge for
a new bi-directional meter and protection equipment to avoid sending power back on the
utility grid during a power outage.
The most to be benefited from this net metering facility are industry and commercial
customers, which are subject to capacity charge in their electricity bill element. Having
solar generation system at rooftop for this segment of customer will reduce the peak
demand consumption thus reduce the capacity charge and reduce total energy bill.
Another group of beneficiaries of the rooftop solar PV will the big electricity user under
residential category. Malaysia electricity tariff was designed with tier rate which higher
rate for higher tier of energy consumption. Having rooftop solar system will lower down
the energy tier and reduce the electricity bill.
4 MALAYSIA NET ENERGY METERING
Malaysia is implementing 500 megawatts (MW) of capacity for net energy metering
(NEM) beginning 2016 until 2020.
Malaysia net-energy metering program is open to all electricity consumer and applicable
for existing or newly built premises.
The objectives of introducing the Malaysia NEM policy are:
• To encourage broader community involvement and growth of decentralized Solar Photo
Voltaic (PV) systems.
• To encourage job creation in the downstream Solar PV market segment.
• To provide further impetus to growth of clean technology in the Malaysia.
• To reduce carbon emissions.
Malaysia net-energy metering (NEM) mechanism will allow excess energy from rooftop
solar generation to be exported to the utility distribution grid. The NEM consumer will not
paid for export of excess energy to the grid, but will be given credit in Ringgit Malaysia
(local currency) for consumption of same amount of energy later. These monetary credits
could be carried forward from one billing period to another, for so long as the consumer
has a legal contract for the supply of electricity by utility.
To kick start the Malaysia Net-Energy Metering program, the first 500MW of the
installation will be ‘simple net-metering’ where the exported units are simply subtracted
from the consumption bill, and no monthly fixed fees to be paid by the NEM consumer.
The exported unit will be credited at utility displaced cost.
It is envisioned that after the 500 MW target is reached, the new NEM entrant would have
to pay a monthly fee to remain connected to the grid, the fee to be determined through a
study on the costs of grid connection absorbed by utility.
The Malaysia net-energy metering program is open to residential, commercial and
industrial customers. Only rooftop installation (with or without storage) allowed and
ground-mounted or any other means will be discarded.
Install capacity for residential consumer is limited to 6 kW and maximum capacity for
industrial and commercial consumer is cap at 75% of their maximum demand or 1MW
capacity whichever is lower.
All the installation cost such as interconnection cost, metering cost, etc will be borne by
the NEM customer.
5 COMMERCIAL STRUCTURE OF MALAYSIA NET-ENERGY METERING
Provisions for energy accounting and commercial arrangements for Malaysia Net-Energy
Metering is in accordance to Malaysia Electricity Supply Industry (MESI) Acts &
Regulations 2014.
The excess energy produced by the customers during a billing period shall be carried over
to the next billing period in the form of energy credits, which can be utilized for calculation
of net electricity, injected or consumed in the future billing periods. At the end of a
settlement period, the excess energy generated shall be adjusted in the subsequent billing
period. The energy accounting/ settlement period shall be of two years as per the Energy
Commission regulations.
The billing structure for Net-Energy Metering consumer is as follows:
Item RM Total Payable
kWh import from utility x tariff A TNB supply
(A + B + C + D + E) Good & Service Tax (GST) 1: (A+E) x 6% B
RE Fund: A x 1.6% C
Penalties D
Imbalance Cost Pass Thru E
kWh export x solar rate F NEM Rebate
(F + G) GST 2: F x 6% G
Total Payable (A + B + C + D + E) – (F + G) Table 1: billing structure for NEM customer in Malaysia
NEM customer will only receive one bill monthly. If NEM Rebate (RM) more than utility
supply (RM) then customer is will pay the net amount to utility. If NEM Rebate (RM) more
than utility supply (RM) then customer is given monetary credit in the next bill.
Unused credit amount will rollover up to end of calendar year. At the end of each calendar
year, change in tariff category or upon the termination of NEM contract with utility, any
remaining credit will be adjusted to zero.
The credit rate for energy excess to utility classified into two categories based on utility
displaced cost. For low voltage connection, credit rate is at RM0.31/kWh and medium
voltage connection rate is RM0.238/kWh (note: RM4.0 = USD1).
6 MALAYSIA NEM IMPACT ASSESSMENT METHODOLOGY
Impacts of net-energy metering (NEM) from roof top solar are complex, and discussions
of these issues are invariably argumentative. In the interest of ensuring that the findings
from this study are interpreted and applied appropriately, the key parameter of data
collection governed as below:
The data and information for this study contain relatively high level of detail of national
utility tariff derivation and revenue collection but less detail in company internal production
and operating cost. As a result, the impacts of net-energy metering from roof top solar on
utility actual cost-of-service are based on a rougher set of assumptions than what might be
possible with detail actual operations model.
The model configured for this study, captures financial effects at the utility level, not at the
customer segmentation level (ie industry, commercial and residential segment of
customer). As such, the study do not directly quantify cross-subsidization among customer
segment, although the modelled impacts on average retail electricity rates may, under many
of the scenarios, be considered a proxy for the impacts on non NEM customers from various
segment.
The analysis is focused narrowly on the financial impacts of NEM customer on utility sales
and ratepayers by the implementation of net-energy metering. It does not analyse costs and
benefits for customers with NEM systems and therefore does not consider costs that NEM
customer incur for their system nor any broader social benefits (e.g., reduced emissions,
economic development, energy security).
7 IMPACT OF NET-ENERGY METERING FOR THE CONSUMERS AND TO THE
MALAYSIA UTILITY
Implementation of net-energy metering in Malaysia came with both benefit as well as
challenges. In this regard, these are impact of net-energy metering to the customers and to
the utility:
7.1 Impact of Net-Energy Metering to the Customers
Net-energy metering facility is viable for heavy electricity users who have to pay exorbitant
rates for the higher tier blocks of units (kWh) they consume. Although the initial investment
is much higher to install a rooftop solar facility, the payback period would be very low for
heavy electricity users.
Solar power generation is very much intermittent in nature. The facility produce electricity
when good solar irradiation. Conversely, when the irradiation is not good, the facility will
not produce power and in a typical intermittent type of generation system a bank of batteries
is needed to store the energy for those times. But, the customers having net-energy metering
facility can use the grid to buy power during times when their own systems are not
producing enough energy to meet their needs as well as it allows them to receive value for
the electricity they produce without installing expensive battery storage systems.
7.2 Adverse Financial Impact to Utility and customers
Malaysia electricity industry is undergoing incentive-based regulation (IBR) in an effort to
improve industry efficiency which has been implemented effective January 2014.
Through this framework, average base tariff for a regulatory period of four years is set
based on forward-looking approach of matching revenue requirements with efficient
forecast costs. Next revision period for IBR will be 2018.
Implementing NEM at this point (2016) would lead to adverse financial impact and revenue
loss to utility since the sale of electricity under IBR mechanism has already been ‘locked’
into the tariff calculations. This will give rise to insufficient returns to utility and may lead
to insufficient finds necessary for infrastructure development
Further, implementing NEM in a big way will increase tariff to customers since less sale
will need to recover fixed costs of generation, transmission and distribution which have
been committed. Ideally implementation of NEM must be undertaken together with the
overall planning of the power sector to ensure that investment are not ‘stranded’.
Implementation of NEM should also take into consideration the tariff design of the
electricity sector to address the tariff re-balancing aspect in particular the recovery of fixed
cost to avoid ‘stranded asset’. These impacts pertain to the recovery of stranded investment
(generation, transmission and distribution infrastructure) and provision of inherent cross
subsidy (inter sector, region, income) in current tariff structure. It’s expected revenue loss
is about RM 714mil per year and the stranded investment affected is estimated to cost
RM306mil per year.
7.3 Impact on Utility system reliability
Utility is committed to keep the lights on for the nation at all condition and times, as
electricity is the engine of economic and social well-being. This obligation is inherent in
the technical requirement imposed on the spinning reserve and operating reserve that
safeguard the operation and reliability of the grid operation especially during the peak
demand period.
RE technology particularly solar still has certain limitation on supply reliability and
consistency, which is dependable on external uncontrollable factors such as weather
conditions. Thus, NEM will impact the grid operation through effect on spinning reserves,
operating reserves and reverse power flow.
7.4 Impact on the Utility investment in generation capacity requirement
In relation to generation capacity, the introduction of net-energy metering will not minimize
the capital expenditures required for power generation plant-up in the medium to long term
as new generation capacity for Malaysia requirement has been committed until 2020 with
sufficient reserve margin.
8 SUSTAINABLE APPROACH TOWARD IMPLEMENTATION OF NEM IN
MALAYSIA
From utility perspective, a sustainable mechanism must be introduced for the
implementation of NEM. The sustainable mechanism is crucial in order to maintain balance
in the electricity tariff and o ensure that non-NEM customers are not excessively burdened.
A right mechanism will ensure a sustainable implementation of NEM without burdening
others customer.
8.1 The balance of tariff must be maintained
The current Malaysia electricity tariff was set based on the pre-determined demand volume.
When this volume reduces due to NEM, the building blocks of the tariff structure are
disrupted. Hence, in order to maintain the balance tariff, the cost per unit of energy will
now have to be distributed across a shrinking customer base. This increase in tariff will
therefore have to be borne by everyone, including NEM customers who utilise the network
system.
Based on the NEM quota of 100MW per year, the estimated unaccounted loss to the system
is estimated to be RM1.3billion for the period of 2016 to 2020, and expected to increase
further.
8.2 A review on the current tariff mechanism will ensure customers of all sectors are
protected
Currently, there exists an inconsistency in the cost revenue structure in the Malaysia
electricity tariff design. The fixed cost element which form 60% of the total cost can only
be recovered via 25% of the total revenue element. The remaining fixed cost can be
recovered via the revenue element as illustrated below:
In addition, there is a heavy cross-subsidy among various customer groups. At the moment,
the Commercial, Industrial and Agriculture groups are heavily subsidizing the Domestic
and Mining groups. While the current tariff structure was designed to relieve the tariff
impact of Domestic customers through cross-subsidization, inefficient NEM
implementation would disrupt this configuration.
Effectively, Domestic customers who are most likely non-NEM customers, will have to
bear the cost of the unaccounted losses due to NEM. Therefore, it is commendable that
these concerns are appropriately and efficiently addressed to avoid unnecessary burden for
non-NEM Domestic customer.
The best way to address these concern is by reviewing the whole tariff design taking into
account the cost of supply for different customers at different voltage levels. However, the
Malaysia electricity tariff review can only be implemented in scheduled Regulatory Period,
thus the interim balancing measure must be undertaken by energy authority.
8.3 Introduction a Grid Fixed Charge for NEM customer to restore balance to the tariff
Utility has made proposal for the implementation of a Grid Fixed Charge (GFC), which is
effectively a charge for developing and maintaining the grid for all customers. This GFC is
to be introduced to only the industrial and commercial customer groups to ensure that fixed
grid charge are recovered equitably.
The introduction of grid fixed charge will recognize the value of the grid fixed cost since
the Industrial and Commercial customers will still need to rely on supply from the grid in
the event there is no generation from solar PV. This is deem a more targeted and fair
mechanism to ensure a sustainable implementation of net-energy metering.
Cost Revenue
Fixed Cost
(60%)
Variable
Cost (40%)
Cost
Fixed
Revenue
(25%)
Variable
Revenue
(75%)
Revenue
9 CONCLUSION
Malaysia is embarking on net-energy metering program in a big way. 500MW capacity is
targeted in first phase of five years period to drive solar industry in the country. The
development of such ambitious target will impact the utility economically and subsequently
the utility ratepayer.
The concept of net energy metering is simple, customers only pay the utility the difference
between their usage and their solar generation. But the impact of net-energy metering are
anything but simple.
These impacts evaluated under a base-case set of assumptions under a wide range of
sensitivity cases that considered within the utilities’ operating and regulatory environments.
The findings from this assessment suggest several implications. The energy sales expected
to drop and capital interment deferred subsequently affected utility return on investment.
This scenario may create pressure on utilities to address shareholders concerns about the
erosion of profits caused by net-energy metering.
Give the complex set of issue by net-energy metering, regulator may wish to address the
concern from the electricity rate-making process perspective. The study suggested that
these impacts are highly dependent upon the specifics of the utility operating and regulatory
environment, which will be important for regulator to consider the particular conditions of
any new tariff formulation which are; change in utility operating cost and change of service
for non-participating customer as well as fixed charge for net-energy metering customer
for utility asset utilisation (cable, poles, etc).
From this perspective, the study indicated that net-energy metering penetration level at
utility network will be proportionate to magnitude of cost variables that will give specific
indicator impact to the ratepayer as whole.
10 RECOMMENDATIONS
Based on the aforementioned facts and finding, the followings are recommended for
betterment of Net-Energy Metering implementation in Malaysia;
a) Benchmarking on several measures taken by utilities around the world, Malaysian
utility prefers a systematic and gradual approach in handling net-energy metering. As
such, net-energy metering implementation should incorporate assessment period
(learning curve), development and optimisation pace.
b) For the first assessment period, the net energy metering capacity should be limited to:
12kW for domestic customer. For Commercial and Industrial customers, the capacity
is <75% of max demand or max 1MW whichever is lower. The capacity shall be less
than declared Maximum Demand such that to limit the electricity export capacity while
impact assessment will be monitored.
c) Credit rate (utility buying price for access energy from NEM) is at utility Displaced
Cost (DC) is considered as sufficient and quite generous, which includes the
proportional cost of avoided Generation cost, Transmission and Distribution. It’s
recommended for the rate to be reviewed accordingly based on overall assessment
impact of NEM to utility and non-NEM customers.
d) It’s recommended that the authority to review the NEM Policy & Guideline every 2
years on NEM terms and condition such as tariff rate, credit rollback, penetration,
capacity quota is required to optimise NEM mechanism according to latest situation
and scenario
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